Hydraulic jack



Patented Dec. 14, 1948 y UNITED .STATES PATENT OFF'E CE HYDRAULIC JACK.Louis Y Berg, Birmingham, .Mieh.

Application SeptemberZ'l, 1946, Serial No. .698,522

(Cl. 254-f93) .2 Claims.

' This invention relates to improvements in hydraulic jacks and in'particular to improved hydraulic bumper jacks for automobiles. y

The 'primary `object of the vinvention is toprovide/an improvedhydraulic jackin which the entire hydraulic pumping and valve mechanismis located in a novel, compact-and readily manufacturedzhead.

Another object of theinvention is to provide an improved hydraulic`bumper jack in which the .bumper engaging means is readily adjustableto the bumper prior to the jack being operated Ito lif-tfan automobile.A further object of the invention is to `provide yan improved .hydraulicbumper jack which is simple .in construction,.ipositive :in operationand inexpensiveito manufacture.

Other :objects `of the invention will vbecome apparent Vby reference tothe following detailed description taken vin connection with theVaccompanying drawing, in which:

Fig. 1 is a side elevational View V`of .a r.hydraulic bump-er jackembodying `the invention with portions thereof br-oken away toillustrate the construction.

Fig. 2 is a horizontal sectional view taken on'the yline 2--2 of Fig. 1.

Fig. 3 is a horizontal sectional view taken on the line 3--3 of Fig. 1.

Fig. 4 is -a fragmentary sectional view taken on 'the'lline4-4 of Fig.2.

Referring now to the drawing wherein vlike nu merals refer to like and`corresponding parts `throughout the several views, the particular rem'bodiment of the inventiondisclosed for the purpose of illustrationcomprises a base I0, `a general- "ly vertically disposed piston IIhaving a ball l2 formed on the lower vend thereof engaged in a socket Lformed in the said base Ill, a cylinder I4 `into which the 'piston I Iis reciprocatingly mounted, a housing I5 forming a reservoir I6 for oilor ymentof the said cylinder .I4 with respect -to the piston I Land amanu-ally operated lowering valve -2llconnecting the reservoir I6 with.the upper end 'of-the said cylinder I4 for lowering thesaidhousing I5under load, an -adjustable bum-perengaging arm 21 slidably mounted onsaid housing I5, fand l a cam 22 for releasa'bly securing the saidslidable.v

on the. said housing 15.

, The top ci the -verticallydisposed piston -I'I has a fself sealing:head E3 .of neoprene, leatherror the like :secured .on the upper `end.thereof which is suitably lipped to flex against the Wall .of thecylinder 'I4 `and provide a seal between ythe top ofthe piston l! andthevcylinder 'I4 'when fluid under pressure `'is 'forced from the pumpEhead :il into the cylinder I4. The said piston head 23 `has washers '24and 25 disposed aboveand below the base thereof and is .secured to 'the.top vof fthe piston `Il .by means of a stud 26. The bottom 4of thecylinder I4 and `the bottom of the housing I5 :are xed in sealedrelationship to a guide sleeve 21.7 disposed around the piston Inl.`Packing 28 squeezed between thelower Vendofithe cylinder It and apacking .nut 129 slidably disposed over=the .piston II andthreaded into.the guide sleeve "2l prevents 'leakage of iluld from the lower end ofthe said cylinder I4 as it ymoves upwardly :and :downwardly vwithrespect to the piston -I I. The upper `end of the Icylinder vI4 isthreadedzat Sil into a Cylindrical recess provided in .the'bottom of the`pump head Il and the .housing I5 is pressed, lbrazed orfotherwisesecured at'SI to -therlowerend ofthe said `pump head il, all as bestshownin Fig. l.

The bumper-.engaging arm generally designated bythe numeral El in Fig. 1comprises a-sleeve 32 `slidably disposed on the housing I 5 with a pairof laterally spaced later-ally protruding vheolcs .33

'adapted -to engage -a bumper of an automobile formed integral with thesaid sleeve 32 4and extending laterally therefrom. A -pin 34 extendsthrough .both ofthe said spaced protruding hooks v33 near the housing I5and has journaled .thereon an eccentric or cam 22 having an operatinglever ,55 xed..thereto. By moving the operating lever ..35 from Athefull line position shown in Fig. 1 to the dot and dash line position350, the cam 22 isbroiiglit into engagement with Ithe'housing I5 andthe'bumper engaging arm 2i becomes reizcovaloly `ixed with respect thereto.

,The pumphead Il comprises a cylindricallower portion 35 and a pair oflaterally spaced .rec-

tangular upright members .3l integral vtherewith connected at theirl.top by a `bridge 38. Each upright member y5l is vertically bored fromthe .top thereof and lined with tubular liners 35 to form cylinders 483-and 4I which are iitted with pistons 42 and 43. The upper end oi eachpiston is ilattened at 44 to accommodate links Il5 which are connectedby link pins 45 and il to the pistons 42 Iand l43- andthe .rocker rarmi8 respectively. The .said rocker arm 48 is pivoted on a transverseviul- .cr.um..pin49 which extends through the rocker arm 48 and thebifurcated fulcrum support 50. The end 480 of the rocker arm 48 which isbroken away in Fig. 1 extends outwardly a suiiicient distance to serveas a lever for pivoting the said rocker arm 48 about its fulcrum 49,thus causing the pistons 42 and 43 to reciprocate in the cylinders 49and 4I respectively.

A suitable annular gasket or ypacking 5| of neoprene or the like ispositioned around each piston 42 and 43 and is squeezed between theupper ends of the liners 39 and a packing nut 5|0 threaded in the upperend of each cylinder 40 and 4l to provide a leakproof joint around thesaid pistons 42 and 43. Each piston 42 and 43 is preferably shoulderedat its lower end 52 and has a central depending button 53 formed on thelower end thereof over which is disposed a cup shaped self sealingpiston head 54 of neoprene, leather or the like which is suitably lippedto flex against the walls of the cylinders 49 and 4| to provide a sealbetween the top of the pistons 42 and 43 and the said cylinders 49 and4I respectively during the compression stroke of the said pistons 42 and43.

Each of the cylinders 40 and 4I is provided with a vertically disposedinlet port 56 and 57 respectively which are `connected by a transverseinlet passage 55 to a vertical inlet passage 560 which in turn isconnected to the eduction tube I8 which extends to a point near thebottom of the reservoir I6 located between the cylinder I4 and thehousing I5. Normally closed spring loaded ball check valves 58 and 59are disposed in the transverse inlet passage 55 between the verticalinlet passage 569 and the vertical inlet ports 56 and 51 of thecylinders 40 and 4I respectively, all as best shown in Figs. 1, 2, 3 and4.

Each of the cylinders 40 and 4| is also provided with verticallydisposed outlet ports 60 and 6| respectively which are connected bytransverse outlet passages 62 and 63 to vertical outlet passages 64 and65 normally closed by spring loaded ball check valves 65 and 6'! whichare urged closed by a common inverted cone spring 68 disposed betweenthe head of a stud 69 and a rocker washer I0 which maintains either oneor both of the said ball check valves 65 and Bl closed at all times, allas best shown in Figs. 1, 2 and 3.

After the jack has lifted an automobile by its bumper or other object tothe desired height, the hydraulic jack is lowered by turning thelowering valve Sill to the position indicated in Fig. 1 with thepassages 'II and 'I2 in communication with each other whereby to letiluid flow from the cyl inder I4 above the head 23 of the piston to thereservoir E6. Obviously, during pumping to raise the jack, the loweringvalve 20 is closed by turning the same 90 degrees from its positionshown in Fig. l.

From the foregoing detailed description, the operation of the hydraulicbumper jack is obvious, the improved construction being simple andinexpensive to manufacture and requires substantially no maintenance.

Although but one embodiment of the invention has been disclosed anddescribed in detail, it is obvious that many changes may be made in thesize, shape, arrangement and detail of the various elements of theinvention without departing from the spirit and Scope thereof as definedby the appended claims.

claim:

l. A hydraulic jack comprising a base, a piston connected to said baseextending upwardly therefrom, a piston head on said piston, a cylindersubstantially coextensive of said piston reciprocatingly mounted oversaid piston, a housing over said cylinder, a pump head on said housingand said cylinder forming a reservoir around said cylinder including aneduction tube extending into the said reservoir to a point substantiallyat the bottom' thereof, a multi-piston pump in said pump head includingintake and outlet valves for each pump cylinder between the saidreservoir and the said jack cylinder `respectively employed to withdrawi'luid from said reservoir and force the same into said cylinder abovesaid piston head whereby to raise the said cylinder and housing on saidpiston with respect to the said base, an independent spring urging eachintake valve closed, a rocker washer bridged between the said outletvalves and a common spring acting through said rocker washer urging saidoutlet valves closed and permitting either one or the other to open,means slidably adjustable along said housing adapted to be removablyfixed to the desired position therealong for engaging objects of variousheights, and a manually operated lowering valve normally closed whichwhen open permits uid to flow from said cylinder to said reser- Voirresponsive to weight lifted by said jack.

2. A hydraulic jack comprising a base, a piston connected to said baseextending upwardly therefrom, a piston head on said piston, a cylindersubstantially coextensive of said piston reciprocatingly mounted oversaid piston, a housing over said cylinder, a pump head on said housingand said cylinder forming a reservoir around said cylinder including aneduction tube extending into the said reservoir to a point substantiallyat the bottom thereof, a multi-piston pump in said pump head includingintake and outlet valves for each pump cylinder between the saidreservoir and the said jack cylinder respectively employed to lwithdrawiluid from said reservoir and force the same into said cylinder abovesaid piston head whereby to raise the said cylinder and housing on saidpiston with respect to the said base, an independent spring urging eachintake valve closed, a rocker washer bridged between the said outletvalves and a common spring acting through said rocker washer urging saidoutlet valves closed and permitting either one or the other to open, thesaid cylinder having a by-pass therethrough near the bottom thereofwhereby to cause fluid to circulate from said cylinder to said reservoirafter the said cylinder and housing have been raised to a predeterminedheight, means slidably adjustable along said housing adapted to beremovably xed to the desired position therealong for engaging objects ofvarious heights, and a manually operated lowering valve normally closedwhich when open permits iluid to flow from said cylinder to saidreservoir responsive to weight lifted by said jack.

LOUIS BERG.

REFERENCES CETED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,925,704 Pfauser Sept. 5, 19332,164,621 Pfauser July 4, 1939 2,170,464 Rosenberry Aug. 22, 19392,195,045 Bernay Mar. 26, 1940 2,261,438 Harwood Nov. 4, 1941 2,351,145Pearson June 13, 1944

